Bacillus sp. D747 strain, plant disease controlling agents and insect pest controlling agents using the same and control method using the agents

ABSTRACT

The present invention relates to a novel strain of  Bacillus  sp. D747 (deposited as FERM BP-8234) and methods for controlling plant diseases and insect pests, comprising administering cultures of  Bacillus  sp. D747 (including the viable bacteria) or viable bacteria isolated by culturing, on the plant parts such as roots, stems, leaves, seeds, and the like, or in the culture soil.

TECHNICAL FIELD

The present invention relates to a Bacillus sp. D747 strain and toapplications thereof. More particularly, the present invention relatesto an agent for controlling a plant disease and/or an agent forcontrolling an insect pest comprising, as an active bacterium, theBacillus sp. D747 strain exhibiting effects of controlling plantdiseases and effects of controlling pests, and relates to a controlmethod using these control agents.

BACKGROUND ART

As examples of methods for controlling plant diseases and pests, mentionmay be made of physical control methods and field husbandry controlmethods which employ crop rotation or solar heating, chemical controlmethods using agrichemicals, control methods utilizing disease-resistantvarieties, biological control methods using attenuated viruses orantagonistic microorganisms on pathogenic fungi, and the like. Amongthese methods, research and development for agrichemicals andparticularly organo-synthetic fungicides have been significantlyimproved in recent years, and many agents having high potency andexhibiting various effects are continuously being developed.Furthermore, various application methods have also been provided. Thechemical control methods using these have greatly contributed tocontrolling plant diseases, saving labor in controlling operations, andthe like, and have been widely employed. However, recently, it isobserved in some crop plants and diseases that controlling effectsprovided by chemical control methods are reduced due to the appearanceof so-called chemical-resistant pests, and this has become a problem. Inaddition, as a result of continuous cropping forced by spreading ofmonocultures, outbreaks of infectious diseases via soil, which arebelieved to be difficult to control with agrichemicals, have become aserious problem in various locations. Furthermore, in methods in whichlarge amounts of agrichemicals are repeatedly employed, chemicalsubstances, which are not naturally present, are released into theenvironment. For this reason, it has been understood that not onlychemicals which are directly toxic to animals and plants, but alsonon-toxic chemicals, can cause adverse effects on the environment.

As described above, the control of diseases with agrichemicals is highlylikely to reduce controlling effects due to the appearance of resistantpests. In this case, it is necessary to develop new fungicides. Inaddition, with respect to controlling diseases which are believed to bedifficult to control with agrichemicals, alternative means or means usedtogether with other methods must be implemented. In addition, it isdesired that a control technique which is safer in view of theenvironment be established.

Recently, in light of these circumstances, controlling methods dependingon the use of agrichemicals are being reconsidered, and biologicalcontrol methods utilizing microorganisms (so-called biological controlagents) which are believed to be safer for the environment compared withagrichemicals have been proposed, and some of these have been put topractical use.

In research for biological control of plant diseases, utilization ofattenuated viruses, utilization of attenuated pathogenic ornon-pathogenic type microorganisms of pathogenic microbes, utilizationof antagonistic microorganisms, and the like, have been attempted. Amongthese, there is much research on utilization of antagonisticmicroorganisms. In addition, there are many reports on research forcontrolling diseases among the antagonistic microorganisms in the genusBacillus. However, the genus Bacillus has not been found to exhibiteffects for controlling a broad spectrum of diseases.

DISCLOSURE OF THE INVENTION

An object of the present invention is to isolate a novel strainexhibiting effects of controlling diseases of plural varieties of plantdiseases and/or controlling insect pests.

Another object of the present invention is to provide an agent forcontrolling a plant disease and/or an agent for controlling an insectpest, comprising, as an active bacterium, the aforementioned strain,which can be effectively employed as a biological control agent.

Another object of the present invention is to provide a method forcontrolling plant diseases and/or insect pests using the agent forcontrolling a plant disease and/or the agent for controlling an insectpest described above.

The present inventors discovered that a novel strain belonging to thegenus Bacillus isolated from nature exhibits effects of controllingseveral varieties of plant diseases and exhibits effects of controllingpests without harming plant growth, thus completing the presentinvention.

The present invention relates to a strain described below, an agent forcontrolling a plant disease and/or an agent for controlling an insectpest, and a method for controlling plant diseases and/or controllinginsect pests.

-   (1) A Bacillus sp. D747 strain.-   (2) An agent for controlling a plant disease characterized by    comprising the Bacillus sp. D747 strain as an active bacterium.-   (3) An agent for controlling an insect pest characterized by    comprising the Bacillus sp. D747 strain as an active bacterium.-   (4) A method for controlling a plant disease and/or an insect pest    characterized by employing the agent for controlling a plant disease    described in (2) above and/or the agent for controlling an insect    pest described in (3) above.    [Isolation of the Bacillus sp. D747 Strain and Deposition Thereof]

The Bacillus sp. D747 strain of the present invention is a strainisolated from the air in Kikugawa-cho, Ogasa-gun, Shizuoka-ken, JAPAN.As a result of identification of the strain in view of the bacterialcharacteristics described below in accordance with Bergey's Manual ofSystematic Bacteriology, Volume 1 (1984), it was believed that it was anovel strain belonging to the genus Bacillus, and might be a Bacilluscereus. For this reason, the strain was deposited as “Bacillus cereusD747” at the Agency of Industrial Science and Technology, NationalInstitute of Bioscience and Human Technology, on Nov. 28, 2000.

However, after that, it was again studied in detail as to whether or notit belonged to Bacillus cereus. As a result, the study provided only theconfirmation that it belonged to the genus Bacillus. For this reason, anotification of change of the name of the strain to “Bacillus sp. D747”was submitted on Apr. 1, 2002.

Therefore, the Bacillus sp. D747 strain (hereinafter, simply referred toas the “D747 strain”) according to the present invention was depositedat the National Institute of Advanced Industrial Science and Technology,International Patent Organism Depositary as “Bacillus sp. D747” withAccession Number “FERM P-18128”, and was then transferred to bedeposited under the Budapest Treaty on Nov. 8, 2002, as “Bacillus sp.D747” with new Accession Number “FERM BP-8234”.

[Bacterial Characteristics of the D747 Strain]

The bacterial characteristics of the D747 strain according to thepresent invention are described as follows. The tests for the bacterialcharacteristics were carried out in accordance with Bergey's Manual ofSystematic Bacteriology mentioned above.

(A) Morphological Characteristics

-   Morphology: bacillus-   Size: width=1.0 to 1.2 μm; length=3 to 5 μm-   Mobility: +-   Flagellar adherent condition: periphery flagella-   Endospore: +-   Spore position: center-   Spore swelling: −

(B) Cultural Characteristics

-   Color of colony: white to pale brown-   Culturing in a bouillon agar plate medium: A white to cream colored    colony is formed, and the surface thereof is wrinkled.

(C) Physiological Characteristics

-   Gram's stain stainability: +-   Nitrate reduction: +-   MR test: −-   VP test: +-   Indole formation: −-   Starch hydrolysis: +-   Citric acid assimilating ability: +-   Inorganic nitrogen source: +-   Oxidase: −-   Calatase: +-   Growth pH 6.8, bouillon medium: +-   Growth pH 5.7, bouillon medium: +-   Growth temperature, 30° C.: +-   Growth temperature, 50° C.: −-   Growth NaCl concentration, 2%: +-   Growth NaCl concentration, 5%: +-   Growth NaCl concentration, 7%: +-   Aerobic growth: +-   Anaerobic growth: −-   O-F test: O-   York reaction: −-   Acid formation from glucose: +-   Acid formation from mannitol: −-   Acid formation from L-arabinose: −-   Acid formation from D-xylose: −-   Gas formation from glucose: −-   β-galactosidase: −-   NaCl and KCl requiring property: −    [Culturing of the D747 Strain]

In the culturing method of the D747 strain employed in the presentinvention, the kinds of media, culturing conditions, and the like, canbe appropriately selected. As examples of media, mention may be made of,for example, a medium including glucose, peptone, and a yeast extract,and the like, in addition to a common medium such as a bouillon medium.In addition, solid media such as a slant medium, a plate medium, and thelike, including agar, in addition to a liquid medium, may be employed.By culturing, the D747 strain multiplies, so that a desirable amount ofthe strain can be obtained.

As a carbon source of the medium, all materials into which theaforementioned strain can assimilate may be utilized. As examplesthereof, mention may be made of various synthetic or natural carbonsources which the D747 strain can utilize, in addition to sugars such asglucose, galactose, lactose, sucrose, maltose, a malt extract, and astarch hydrolysate.

As a nitrogen source of the medium, organic nitrogen-containing productssuch as peptone, bouillon, yeast extract, and the like, and varioussynthetic or natural products which the D747 strain is capable ofutilizing can be utilized.

In accordance with common methods for culturing microorganisms,inorganic salts such as sodium chloride, phosphates, or the like; saltsof a metal such as calcium, magnesium, iron, or the like; micronutrientsources such as vitamins, amino acids, or the like; can be added, ifnecessary.

Culturing can be carried out under aerobic conditions such as shakeculturing, aeration culturing, or the like. The culturing temperatureranges from 20 to 30° C., and preferably ranges from 25 to 30° C.; thepH ranges from 5 to 8, and preferably ranges from 6 to 7; and theculturing period suitably ranges from 1 to 4 days, and preferably rangesfrom 2 to 3 days.

The Bacillus sp. D747 strain according to the present invention exhibitsproperties of controlling various plant diseases and controlling pestsby administering cultures thereof (including the bacteria per se) ortreated products thereof (a mixture of a culture and other ingredients,or the like), or bacteria isolated by culturing (bacteria obtained bytreating a culture by centrifugation, or cleansed bacteria thereof, orthe like) or treated products thereof (a mixture of the isolatedbacteria and other ingredients, or the like), or treated products ofthose described above (a diluted product thereof with a liquid or asolid, or the like), on the plant parts such as roots, stems, leaves,seeds, and the like, or in the culture soil.

The D747 strain of the present invention can control plant diseasescaused by bacteria and fungi belonging to genera Oomycetes, Ascomycetes,Basidiomycetes, and Deuteromycetes.

As examples of pest fungi causing diseases which the D747 strain cancontrol, mention may be made of, for example, Pseudoperonospora such asPseudoperonospora cubensis, Venturia such as Venturia inaequalis,Erysiphe such as Erysiphe graminis, Pyricularia such as Pyriculariaoryzae, Botrytis such as Botrytis cinerea, Rhizoctonia such asRhizoctonia solani, Puccinia such as Puccinia recondite, Septoria suchas Septoria nodorum, Sclerotinia such as Sclerotinia sclerotiorum,Pythium such as Pythium debaryanum Hesse; as bacteria, Burkholderia suchas Burkholderia plantarii; and the like. It should be understood thatthey are not limited to these examples in the present invention.

In addition, the D747 strain of the present invention can control pestssuch as hemipterous pests, lepidopterous pests, coleopterous pests,dipterous pests, orthopteran pests, isopterous pests, thysanopterouspests, tetranychidaeous pests, and the like.

As examples of pests which the D747 strain can control, mention may bemade of, for example, hemipterous pests including Pentatomidae(Heteroptera) such as Riptortus clavatus and the like, Cicadellidae suchas Nephotettix cincticeps and the like, Delphacidae such as Nilaparvatalugens and the like, Psyliidae such as Psylla sp., and the like,Aleyrodidae such as Bemisia tabaci and the like, Aphididae such as Myzuspersicae and the like, Pseudococcoidae such as Pseudococcus comstockiand the like; lepidopterous pests including Torticoidea such as HomonaMagnanima and the like, Cochylidae such as Eupoecillia ambiguella andthe like, Psychidae such as Bambalina sp., and the like, Gracillariidaesuch as Nemapogon granellus and the like, Phyllocnistinae such asPhyllocnistis citrella and the like, Yponomeutidae such as Plutellaxylostella and the like, Pyralidae such as Chilo suppressalis and thelike, Noctuidae such as Heliothis virescens and the like; coleopterouspests including Scarabaeidae such as Anomala cuprea and the like,Coccinellidae such as Epilachna vigintioctopunctata and the like,Curculionidae such as Lissorhoptrus oryzophilus and the like; dipterouspests such as Culex pipiens, Anopheles sinensis, Culextritaeniorhynchus, and the like; orthopteran pests such as Blatellagermanica, and the like; isopterous pests such as Reticulitermessperatus, and the like; thysanopterous pests such as Scirtothripsdorsali, and the like; tetranychidaeous pests such as Tetranychusurticae, and the like; other harmful animals, creatures to be repelled,insect pests in view of sanitation, parasites, examples of which includeGastropoda such as Pomacea canaliculat, Incilaria sp., and the like; andIsopoda such as Armadillidium sp., and the like. It should be understoodthat the present invention is not limited to these examples.

Agents for Controlling Plant Diseases and Agents for Controlling Pests

The agents for controlling plant diseases and agents for controllingpests according to the present invention comprise, as an activebacterium, the D747 strain which can control plant diseases and insectpests as described above. In the agents for controlling plant diseasesand agents for controlling pests of the present invention, the D747strain can be employed alone or in combination with a variant of theD747 strain. The variants have the bacterial characteristics of the D747strain described above, exhibit effects of controlling plant diseases,and exhibit effects of controlling pests. Spontaneous mutant strains,mutant strains produced by using UV rays or chemical mutagen agents,cell fusion strains, and genetic recombination strains can be utilizedtherefor. In the present invention, the D747 strain contained in theagents for controlling plant diseases and the agents for controllingpests also include the variants of the D747 strain.

The term “controlling” in the specification is used to mean not onlypreventing and repelling diseases or pests, but also removing anddestroying them. Therefore, even for plants which have been infected bypathogenic fungi, if the agents for controlling plant diseases areapplied thereto, the pathogenic fungi can be removed from the plants,and thereby, pathogeny caused by the pathogenic fungi and deteriorationof the diseases can be prevented. In addition, pests can also becontrolled due to the effects of repelling and killing pests.

For the case in which the D747 strain is included as viablemicroorganisms in the agents for controlling plant diseases and theagents for controlling insect pests according to the present invention,it is preferable that the strain be applied to the plant body at aconcentration ranging from 10⁵ to 10¹⁰ microorganisms/ml.

In addition, for the case in which a culture of the D747 strain isemployed, the application timing and the application quantity thereofmay be appropriately determined in accordance with the case of theviable microorganisms described above.

In addition, in the agents for controlling plant diseases and the agentsfor controlling insect pests according to the present invention, theD747 strain may be employed alone as the strain, or a culture thereofmay be employed, as formulations in which the strain is diluted with aninert liquid or solid carrier, and surfactants and other auxiliaryagents are added thereto, if necessary. As examples of formulations,mention may be made of granules, fine powders, wettable powders,suspensions, emulsifiable concentrates, and the like. As examples ofpreferable carriers, mention may be made of porous solid carriers suchas talc, bentonite, clay, kaolin, diatomaceous earth, white carbon,vermiculite, slaked lime, siliceous sand, ammonium sulfate, and urea;liquid carriers such as water, isopropyl alcohol, xylene, cyclohexanone,methylnaphthalene, and alkyl glycol; and the like. As examples ofsurfactants and dispersants, mention may be made of, for example,dinaphthylmethanesulfonates, alcohol sulfates, alkyl aryl sulfonates,lignin sulfonates, polyoxyethylene glycol ethers, polyoxyethylene alkylaryl ethers, polyoxyethylene sorbitan monoalkylates, and the like. Asexamples of auxiliary agents, mention may be made ofcarboxymethylcellulose, polyethylene glycol, propylene glycol, gumarabic, xanthan gum, and the like. As examples of protective agents,mention may be made of skim milk, pH buffers, and the like. In thiscase, the amount of the viable microorganisms of the D747 strain and/orthe amount of the cultures thereof, the application timing, and theapplication quantity can be appropriately determined in accordance withthe case of the viable microorganisms described above.

Furthermore, the agents for controlling plant diseases and the agentsfor controlling pests according to the present invention may includeother ingredients such as pesticides, other fungicides, herbicides,plant growth modifiers, fertilizers and manures, and the like, as activeingredients, if necessary. In addition, the agents for controlling plantdiseases and the agents for controlling insect pests according to thepresent invention may include different varieties of strains from theD747 strain, together with the D747 strain.

The agents for controlling plant diseases and the agents for controllinginsect pests according to the present invention can be directly appliedor can be applied after diluting the agents with water or the like. Themethods for applying the agents for controlling plant diseases and theagents for controlling insect pests are not particularly limited. Asexamples thereof, mention may be made of, for example, a method in whichthey are directly sprayed to plants or insect pests, a method in whichthey are sprayed on soil, a method in which they are added to water orfertilizers and manures to be applied to the plants or soil, and thelike. In addition, the amount of applied formulations will varydepending on the diseases to be controlled, insect pests to becontrolled, plants to which they are to be applied, application methods,the nature of occurrence of the diseases or pests, the degree of damage,environmental conditions, the forms of formulations to be used, and thelike. For this reason, it is preferable that the amount of the appliedformulations be appropriately adjusted.

As described above, the Bacillus sp. D747 strain of the presentinvention controls a wide spectrum of diseases and pests, and cancontrol multiple varieties of plant diseases and pests.

The agents for controlling plant diseases and the agents for controllingpests comprising the D747 strain according to the present invention cancontrol plant diseases and pests. For this reason, they can be employedas biological control agents. Therefore, the agents for controllingplant diseases and the agents for controlling insect pests of thepresent invention are highly safe with respect to the environment, andexhibit effects of controlling multiple varieties of diseases and pests.For this reason, they can widely prevent diseases and pests withoutemploying other means for simultaneous use therewith.

BEST MODES FOR CARRYING OUT THE INVENTION

The present invention is described in detail be means of the Examplesdescribed below. However, it should be understood that the presentinvention is not limited to these Examples.

EXAMPLE 1 Culturing of the D747 Strain

The D747 strain was isolated from the air in Kikugawa-cho, Ogasa-gun,Shizuoka-ken, JAPAN. More particularly, in order to isolate themicroorganisms present in the air at Kamo, Kikugawa-cho, Ogasa-gun,Shizuoka-ken, JAPAN, a plate medium containing a potato-dextrose agarwas allowed to stand for 10 minutes with the lid off so as to be incontact with the air. The medium was incubated for 3 days at 27° C., andthe formed colony was isolated. The isolated colony was incubated with ashaker in a medium of a potato-dextrose liquid. The strain exhibitingactivities with respect to plant diseases was discovered, thus resultingin isolation of the D747 strain.

The isolated D747 strain was incubated at 27° C. on a rotary shaker at120 rpm for 3 days in a medium having a pH of 6.0 and comprising 1% ofglucose, 2% of a soluble starch, 0.5% of polypeptone, 1% of a dry yeast,1% of defatted soybeans, 0.2% of KH₂PO₄, 0.2% of NaCl, and 0.3% ofcalcium carbonate. Subsequently, the strains were collected bycentrifugation (10,000×g, for 15 minutes), were suspended in sterilizedwater, and were washed to remove the medium ingredients. The serialprocedures described above were repeated twice. Subsequently, thestrains were again suspended in sterilized water at a concentration ofapproximately 10⁹/ml.

EXAMPLE 2 Test on the Effects of Controlling Infection by Rice Blast

Rice seeds (variety: Aichi Asahi) were sown at a rate of 10 grains eachin clay pots having a diameter of 7.5 cm, and were allowed to grow in agreenhouse. A suspension of the D747 strains produced as described inExample 1 was sprayed at a rate of 10 ml per pot on the rice seedlingsat their 4-leaf stage. After being dried in the air, the seedlings wereinoculated by spraying a spore suspension of rice blast (Pyriculariaoryzae) fungi, and were placed in a moist chamber. On the fifth dayafter the inoculation, the number of lesions on the fourth leaf wascounted, and was evaluated as the extent of lesions on the basis of theevaluation criteria shown in Table 1 described below. The test resultsare shown in Table 2.

TABLE 1 Evaluation A No lesions were observed. B Less than 20% based onthe extent of lesions in the untreated plot C 20% or more but less than50% based on the extent of lesions in the untreated plot D 50% or morebased on the extent of lesions in the untreated plot

EXAMPLE 3 Test on the Effects of Controlling Infection by Rice SheathBlight

Rice seeds (variety: Kinmaze) were sown at a rate of 10 grains each inclay pots having a diameter of 6.0 cm, and were allowed to grow in agreenhouse. A suspension of the D747 strains produced as described inExample 1 was sprayed at a rate of 10 ml per pot on the rice seedlingsat their 2-through 3-leaf stages. After being dried in the air, theseedlings were inoculated with rice sheath blight (Thanatephoruscucumeris) fungi, and were placed in a moist chamber. On the fifth dayafter the inoculation, the heights of lesions were measured, and wereemployed as an evaluation of the extent of lesions. Evaluation wascarried out on the basis of the evaluation criteria shown in Table 1described above. The test results are shown in Table 2.

EXAMPLE 4 Test on the Effects of Controlling Infection by Wheat GlumeBlotch

Wheat seeds (variety: Nourin No. 61) were sown at a rate of 10 grainseach in plastic pots having a diameter of 6.0 cm, and were allowed togrow in a greenhouse. A suspension of the D747 strains produced asdescribed in Example 1 was sprayed at a rate of 10 ml per pot on thewheat seedlings at their 2-leaf stage. After being dried in the air, theseedlings were inoculated with pycnospores of wheat glume blotch(Septoria nodorum) fungi, and were placed in a greenhouse. On the tenthday after the inoculation, the infected area of the first leaf in eachpot was measured, and was employed as an evaluation of the extent oflesions. Evaluation was carried out on the basis of the evaluationcriteria shown in Table 1 described above. The test results are shown inTable 2.

EXAMPLE 5 Test on the Effects of Controlling Infection by Wheat PowderyMildew

Wheat seeds (variety: Nourin No. 61) were sown at a rate of 10 grainseach in plastic pots having a diameter of 6.0 cm, and were allowed togrow in a greenhouse. A suspension of the D747 strains produced asdescribed in Example 1 was sprayed at a rate of 10 ml per pot on thewheat seedlings at their 1.5- through 2-leaf stages. After being driedin the air, the seedlings were inoculated with conidiospores of wheatpowdery mildew (Erysiphe graminis), and were placed on a bench in agreenhouse until an infection measurement was carried out. On the tenthday after the inoculation, the infected area of the first leaf in eachpot was measured, and was employed as the extent of lesions. Evaluationwas carried out on the basis of the evaluation criteria shown in Table 1described above. The test results are shown in Table 2.

EXAMPLE 6 Test on the Effects of Controlling Infection by Cucumber GrayMold

Cucumber seeds (variety: Sagami Hanjiiro) were sown at a rate of 4grains each in plastic pots having a diameter of 6.0 cm, and wereallowed to grow in a greenhouse. A suspension of the D747 strainsproduced as described in Example 1 was sprayed at a rate of 10 ml perpot on the young cucumber seedlings in their cotyledonous stage. Afterbeing dried in the air, the seedlings were inoculated by placing a paperdisk which was immersed in a spore suspension of cucumber gray mold(Botrytis cinerea) fungi on the surface of the cotyledons of thecucumber seedlings, and were subsequently placed in a moist chamber at20° C. On the third day after the inoculation, the infected area of thecotyledons was measured, and was employed as an evaluation of the extentof lesions. Evaluation was carried out on the basis of the evaluationcriteria shown in Table 1 described above. The test results are shown inTable 2.

EXAMPLE 7 Test on the Effects of Controlling Infection by Cucumber DownyMildew

Cucumber seeds (variety: Sagami Hanjiiro) were sown at a rate of 4grains each in plastic pots having a diameter of 6.0 cm, and wereallowed to grow in a greenhouse. A suspension of the D747 strainsproduced as described in Example 1 was sprayed at a rate of 10 ml perpot on the young cucumber seedlings in their cotyledonous stage. Afterbeing dried in the air, the seedlings were inoculated by spraying azoosporangium suspension of cucumber downy mildew (Pseudoperonosporacubensis) fungi, and were subsequently allowed to stand in a moistchamber at 22° C. for 24 hours. On the eighth day after the inoculation,the infected area of the cotyledons was measured, and was employed as anevaluation of the extent of lesions. Evaluation was carried out on thebasis of the evaluation criteria shown in Table 1 described above. Thetest results are shown in Table 2.

TABLE 2 Example Plant Controlling effect No. disease tested by the D747strain 2 rice blast A 3 rice sheath blight A 4 wheat glume blotch A 5wheat powdery mildew A 6 cucumber gray mold A 7 cucumber downy mildew A

EXAMPLE 8 Mortality Test of Lissorhoptrus oryzophilus

A suspension of the D747 strain produced as described in example 1, inan amount of 30 ml, was placed in a plastic cup having a volume of 60ml. Three pieces of rice leaves having a length of 3 cm were floatedthereon. Ten imagoes of Lissorhoptrus oryzophilus were released therein,and the cup was closed with a cover. After it was allowed to stand in athermostatic chamber at 25° C. for 3 days, the number of living pestswas counted. The test was carried out three times. A mortality rate wascalculated by equation (1) described below. A definitive mortality ratewas determined by calculating an average value of the three values. Thetest results are shown in Table 3.

Mortality rate(%)={[10−(the number of living pests)]/10}×100

TABLE 3 Definitive mortality rate (%) Treated with the D747 strain 100No treatments 0

As is apparent from the results shown in Table 2 and Table 3, the plantsto which the agents for controlling plant diseases and the agents forcontrolling insect pests comprising the D747 strain according to thepresent invention were applied exhibited superior controlling effectswith respect to various plant diseases and pests.

INDUSTRIAL APPLICABILITY

The present invention has characteristics in that a novel strain ofBacillus sp. D747 (FERM BP-8234) was discovered. By administeringcultures of the Bacillus sp. D747 strain (including the viable bacteria)or viable bacteria isolated by culturing, on plant parts such as roots,stems, leaves, seeds, and the like, or in the culture soil, outbreaks ofvarious plant diseases in an extremely wide range can be controlled, andpests can be controlled. In addition, the plants on which the agents forcontrolling plant diseases and the agents for controlling insect pestscomprising the D747 strain according to the present invention aresprayed can exhibit superior controlling effects with respect to variousplant diseases and pests.

1. A biologically pure bacterial isolate having all the identifyingcharacteristics of Bacillus sp. D747, deposited under FERM BP-8234.
 2. Acomposition comprising the isolate of claim 1 as an active bacterium andone or more liquid or solid carrier(s).
 3. The composition of claim 2which comprises 10⁵ to 10¹⁰ bacteria of said isolate per mL of saidcomposition.
 4. The composition of claim 2 which is a granule, finepowder or wettable powder.
 5. The composition of claim 2 which is asuspension or emulsifiable concentrate.
 6. The composition of claim 2which is a solid, and wherein said solid carrier comprises a poroussolid carrier.
 7. The composition of claim 2 which is a liquid andcomprises a liquid carrier.
 8. The composition of claim 2, furthercomprising one or more liquid carriers selected from the groupconsisting of water, isopropyl alcohol, xylene, cyclohexanone,methylnaphthalene, and alkyl glycol.
 9. The composition of claim 2,further comprising a surfactant or dispersant.
 10. The composition ofclaim 2, further comprising at least one pesticide or fungicide.
 11. Thecomposition of claim 2, further comprising at least one herbicide. 12.The composition of claim 2, further comprising at least one plant growthmodifier, fertilizer or manure.
 13. A method for treating a fungaldisease in a plant comprising contacting said plant with a compositioncomprising a biologically pure bacterial isolate having all theidentifying characteristics of Bacillus sp. D747, deposited under FERMBP-8234.
 14. The method of claim 13, wherein said plant is rice and thefungal disease is caused by rice blast fungus, Pyricularia oryzae. 15.The method of claim 13, wherein said plant is rice and the fungaldisease is rice sheath blight caused by Thanatephorus cucumeris.
 16. Themethod of claim 13, wherein said plant is wheat and the fungal diseaseis wheat glume blotch caused by Septoria nodorum.
 17. The method ofclaim 13, wherein said plant is wheat and the fungal disease is wheatpowdery mildew, Erysiphe graminis.
 18. The method of claim 13, whereinsaid plant is cucumber and the fungus is cucumber gray mold, Botrytiscinerea.
 19. The method of claim 13, wherein said plant is cucumber andsaid fungus is cucumber downy mildew, Pseudoperonospora cubensis.
 20. Amethod for treating a plant infested with an insect pest, wherein saidplant is rice and said in sect pest is Lissorhoptus oryzophilus.
 21. Amethod for making a composition, comprising culturing the bacterialisolate of claim 1, recovering said bacterial isolate, and admixing saidbacterial isolate with a solid or liquid carrier.